There is an RX7 technical race manual that recommends how to mount the oil coolers for racing applications. Depending on what type of front end you are running - it can be counter-intuitive.
We run 2 in series (we had a lot of debate over series vs parallel etc) and our oil temps stay right in the normal operating range. 270 is cooking if its real.

I have a completely different experience with the radios. That being said, as I mentioned, we have the Sampson harness for the car and different brand antenna.
We have had the Baofengs for probably 6 years now and they get used for snowmobiling (wet, cold), the racecar (hot, wet) as well as for general use at the lake for between the boat and trailer. I have found them to be far superior, especially given the price, to any of the FRS crap that many people sell. In addition to that, can run higher than a 1W radio which are not available in Canada.
YMMV

We are running out of things to spent points on with all the free stuff. We have just about everything we can have on it and are still short of 500 by quite a bit... hmm. Good thing no one else picked our car for us.

Many teams do run Sampson. They definitely have a very affordable plug n play option.
However if you have any kind of electronics experience (aka reading instructions for a programmable radio) you can get a good setup for a fraction of the cost.
We started with the basic set from Sampson. Found it a bit limiting and upgraded to Baofeng programmable radios, external antenna for the car and just used the helmet mic's and the PTT from the Sampson system. Otherwise we scrapped the rest of it.
Sampson has a great product for plug n play. Not the be all end all though.

Our team is the same, though we do have a caveat we've discussed if a person is fully at fault and fully totals the car, they pay more than their fair share of parts/replacement up to i think like $800. I'd have to check my records. and there is the understanding everyone helps with the effort side of things.
So far, we've had some pretty big impacts with stuff (not cars) and the damage has been limited to a control arm, some welding and a few rims.

we bring a bill of sale. Its been signed entirely by people all on our team... but its technically a bill of sale from 3 years ago.
Never needed to show it. We always get mocked by the US border peeps. Coming back the Canadian border gave us a hard time because of our spare engine which the border guard was suspicious about and then he couldnt figure out how to unlock our trailer... he didn't appreciate when we told him we could help him out.
The engine chat went like this?
"what's with the engine in the truck box?"
-its a spare engine for the racecar
"why do you need that?"
-in case the one in the racecar blows up
"no one would have time to change an engine"
-we race in 24 hour races, it only takes us about 6 hours to change it, maybe less
"It doesnt look like its ready to drop in"
-it just needs the carb bolted onto it and fuel lines hooked up and spark plug wires
"I know what it takes to make an engine run". convo done. f'ing moron.
Was very satisfying to watch him unable to unlock the lock despite having our keys while our phones are on the counter going off every few seconds while our emails and texts came in.

But the gains were debatably minimal over a pulsing NA intake if you got creative, made a big enough intake manifold and made it very very thin so be able to almost act as a damper. But all in all the intake restricter was incredibly effective at leveling the playing field across a huge variety of engine types (single, double, 4 cylinder, turbo, non turbo).

This. We've talked with some of the teams in post race tech and asked questions and for the most part everyone has been very willing to share with us what they did and give us hints and tips of what theyve found worked (or didnt) to try and save us some time and money. if you approach them with curioisity and not accusations it also usually helps. Maybe its also because we run a car that not many have anymore but there are few teams that are NOT willing to share. To those teams, my automatic thinking is that there is something being hidden. Though I know, blah blah development time and money but just becuase you tell a team this is what we did, doesnt mean they will have the knowledge, ability or perserverence to actually do that. But understanding what makes a team so fast I think is helpful in enjoying the series. And sometimes its straight up drivers/strategy and execution.
That being said, there is speed creep happening but that honestly is inevitable to some degree. If the car list didn't change, the series can't grow. The older cars are getting harder and harder to find and more expensive. How easy are Z cars to find? RX7s? They used to be plentiful and cheap in Canada and they aren't anymore. Nor are parts easy to find or cheap. Which means different/newer cars or swaps which means more performance. And yes, that means speed creep.
Do I think that there are too many parts being given away for free? Yes. The reason I think this is that before the higher performing stock cars had to choose their upgrades - do we want speed or brakes since we cant have both..which made it possible for the lower performance/older cars to spend their points on both and end up at the same point as the higher performing cars. By giving away so much for free, there is nothing left for us to spend points on EXCEPT for a swap. And this I think is the biggest issue with the rules iterations in the past 2 years.
Other than that I like how the new exec is manaing it. We will stay in Chump for now and since the rules are what they are, we are swapping engines and that should get us back to where we need to be to remain moderately competitive instead of the slowest car on track.